Ring Mandrel w/Groove-Steel This Ring Mandrel is made of case hardened steel, finely polished to a smooth finish. Use with a Rawhide or Plastic Mallets to enlarge the sizes of gold, silver, or copper rings. This mandrel features ring measurements from sizes 1 to 16, in increments of 1/4 size Along with a groove down one side to accommodate rings with mounted stones. Made in USA. Overall length: 13", Ring measurements: 1 to 16, Weight: 2 lbs